Production of polymerization products from vinyl ethers



Patented Dec. 2

PATENT OFFICE 2,104,000 PRODUCTION OF POLYMERIZATION rnont Uc'rs FROM-VINYL ETHERS Walter Reppe and can Schlichtihg, Ludwigshafen-on-the Rhine, Germany,

I. G. Farbenindustrie assignors to Aktiengesellschaft,

- Frankfort-on-the-Main, Germany 000 Drawing. AppiicationNovember 9, 1031, Serial No. 574,040. In Germany June 2'1, 1929 11 Claims.

The present invention relates to the production of polymerization-products from vinyl ethers.

We'have found that polymerization products are obtained in an advantageous manner from vinyl ethers having the general formula B1 Ba b I R/ oR in whichR; is an aliphatic, aromatic or' hydroaromatic radicle, and R1, R2 and R3 are hydrogen atoms or' aliphatic radicles, by contacting the a said vinyl ethers singly, or in admixture with each taining at least 5 carbon atoms, such as alcohols other, with practically anhydrous inorganic acid reacting condensing agents, as for example tin tetrachloride, stannous chloride, aluminium chloride or sulphate, iron chloride, zinc chloride, boron fluoride, boron hydrogen fluoride, silicon tetra chloride, mercury chloride, sodiumbisulphate, potassium bisulphate, alum, sulphuric acid, phos' phoric acid,*hydrochloric acid or hydrofluoric acid. The quantities of the condensing agents employed are generally between 0.001 and 5 per cent of the weight'of the vinyl ether employed but even very small amounts, as for example from 0.001 to 0.5 per cent, of the weight'of the vinyl ether employed, of the condensing agents are sufiicient in most cases to efiect the riolymeriza:

tion. The initial vinyl ethers may be chosen for example from the alkyl, cycloalkyl or aryl ethers of vinyl alcohols, such as methyl-, ethyl-, propyl-,

butyl-, hexylor cyclohexyl, vinyl, propenyl or iso-propenyl ethers and also from the vinyl or alkyl-vinylethers of long-chain alcohols concorresponding to the acids containing up to say 35 carbon atoms, especially of animaland vegetable 'fats and waxes, such as .octyl, decyl, dodecyl, tetradecyl, docosanylor octodecyl alcohols, vinyl ethers of montanol and phenyl, 11- or B-naphthyl or cresyl vinyl ethers, as well as monoand divinyl ethers of the glycols and poly-alkylene glycols, as for example of di-, trior tetraethylene or -propylene glycols'and of higher glycols, such as of octodecandiol. Besides these vinyl ethers of glycols the vinyl ethers of the monoalkyl or arylethers of glycols may be employed as for example the vinyl ethers of ethylene, or propylene, glycol mono-methyl, -ethyl, -butyl, -phenyl or -cresyl ethers, and the corresponding mono-alkyl or aryl ethers of dior'tri-ethylene,

or propylene glycols. Specific compounds of these series are for example-dior tri-ethylene glycol mono-vinyl ethers, dior tri-ethylene glycol di-vinyl ethers and thecorresponding vinyl ethers of 1.2-dior tri-propylene glycols, as well [are almost colourless or pale yellow to brown as di-vinyl ether, and t e di-vinylethers of higher acting condensing agents'deposited or adsorbed" I on adsorptive materials. When employing polymerizing agents of this kind it is-not only possible topolymerize any desired large amount of vinyl ether without the danger of an undue rise of temperature, but it is also possible to separate readily the polymerizing agent employed,-which is of great advantage, and, in particular the polymerization temperature canbe lowered in this way. As adsorptive substances may be mentioned especially adsorptive hydrosilicates, as for- 15 example Florida earth and the, adsorptive hydrosilicates obtainable in commerce as bleaching earths under the trade names Tonsil, Granosil, Terrana, Isarit'or under the registered trademark Frankonit, and also, active carbon, kieselguhr, pumice, precipitated silica (silicon substratum) or silica gel. Bleaching earths having an acid reaction, i. e.', those the. aqueous extract 'of which has a pH value of less than 7, as for example the Bavarian bleaching earths obtainable in commerce under the trade names Tonsil H0, TonsilAC'and Granosil, which possess a small content-of mineral acid from their production or purificationare especially suitable and may be used as-such without further impregnation with acid condensing agents. The polymerization may be carried out in the liquid or; with solid condensing agents or con densing agents solidified by deposition on solid carriers, in the gaseous phase. The reaction in the gaseous phase may be effected with the employment of inert gaseous diluents such as carbon dioxide,.nitrogen, methane or carbon monoxide. On working in the liquid phase it .is preferable to add the condensing agents to the vinyl ethers in small portions, care being taken by cooling for the withdrawal of the heat of reaction. The polymerization proceeds very rapidly especially with strongly acid reacting condensing agents. The polymerization products obtainable products having consistencies ranging from those of viscous liquids to balsams or soft resins and waxes which dissolve in the usual organic solvents. Also the liquid phase reaction may be carried out in order to render it less vigorous, in

the presence of inert organic diluents as for example liquid or liquefied aliphatic or aromatic hydrocarbons, such as benzene, toluene, Xylene,- decahydronaphthalene, saturated ethers, such as diethyl ether, ethyl n-butyl ether, ,di-n-butyl ether or ethyl propyl ether and aliphatic liquid hydrocarbons, such as benzine or like mineral oil fractions, or acetone or esters such as butyl or ethyl acetates.

When carrying out the polymerization it is most advantageous to proceed by first diluting only a small part of the vinyl ether with the solvent, the

condensing agent then being added while stirring. The remainder of the vinyl ether is then caused to flow in gradually, care being taken by suitable cooling that the temperature does not unduly rise, the reaction being generally carried out at from 10 to 120 0., preferably between about 20 and 100 C. When'the whole of the vinylether has been introduced, the reaction solution may be heated under a reflux condenser for some time in order to complete the polymerization. The polymerization products obtained after distilling off the solvents employed are almost the same as the products obtained without solvents. The resinous products left hehind after the distillation may be taken up, for

example in ethyl ether or benzene, and recovered in a pure form after distillingoff the solvent employed. As already mentioned mixtures of different vinyl ethers may be polymerized, the addition of a small amount of one vinyl ether to a large quantity of another providing a considerable alteration in the properties of a polymerization product obtainable by polymerizing singly the vinyl ether used in preponderating quantity in the mixture as regards mechanical strength and solubility.

On working with solid condensing agents de- I posited on adsorptive materials itis preferable to work by introducing the vinyl ether to be polymerized in the gaseous or liquid state at the top of a vertical vessel, capable of being heated and cooled, which is charged with the adsorptive substance serving as the polymerizing agent, preferably in small quantities mixed with inert filler bodies, such as balls or rings of glass, clay and like inert materials. Thepolymerization product may be withdrawn from the lower end of the vessel. For the purpose of obtaining a better withdrawal-of the reaction heat, especially in the case of the lower members of the series (vinyl .adsorptive substances even at room temperature.

Whenemploying less active e. g. very weakly acid condensing agents, as for example Frankonit S,

a slight warming to, say, 40 C. is of advantage.

If the'reaction be carried out in the liquid phase inthe presence of .a liquid diluent, the reaction temperature may be raised to the boiling point of the diluent; in this case the vinyl ether to be polymerized is advantageously gradually added to the diluent which is kept boiling and contains the polymerizing agent suspended therein. On

' working in the vaporous phase temperatures up to 250 C. may be applied but the reaction is preferably carried out also in this case at a temvents for the said compounds.

perature of from 40 to 100 C. in the reaction space.

The resulting polymerization products are more or less viscous liquid, or solid, saturated substances depending on the nature of the'ether employed and on the degree of polymerization and are stable to dilute aqueous acids and alkalies. They may be employed, for coating and adhesive-purposes, as substitutes for oils in oil-filled subsoil or submarine cables and as resins in the production of artificial masses; products from high molecular vinyl ethers may be employed as substitutes for polishing and like waxes of natural origin. The products may also be applied as intermediate layers for compound glass; they can be further employed as softening and plasticizing agents for Indiarubber and rubber-like poly merization products of dioleflnes such as butadiene or isoprene, or for masses from polymerized styrene.

The vinyl ethers, especially in large amounts, can bepolymerized particularly rapidly but without danger of an undue rise of temperature by employing boron halides and boron halide hydrogen halides as for example boron fluoride, chloride or bromide, or boron hydrogen fluoride, in the form of their addition or conversion products with organic oxygen bearing compounds as.

for example ethers, such as diethyl or dibutyl ether, ketones or alcohols (see Gmelins Handbuch der anorganischen Chemie", 8th edition, volume Boron, page 114 et seq.) as the condensing agents.

For the purpose of accurate dosing of the condensing agent, the addition or conversion products of the boron halides are advantageously employedonly in very dilute solutions, as for example about 2 per cent solutions. The alcohols .or ethers employed for the preparation of the said addition products may be employed as sol- The amounts of boron halide addition products necessary for the polymerization are extremely-small and frequently amount to only about 0.001 per cent of the vinyl ether to be polymerized. Thus for example for the polymerization of a litre of vinyl n-butyl ether, only about 1 cubiccentimetre of a2 per cent solution of the addition product of boron fluoride with di-n-butyl ether (which can be prepared by introducing a current of boron fluoride into an equimolecular proportion of din-butyl ether at about 10 C.) in di-n-butyl ether is necessary. vinyl ethers may be carried out in the presence of a solvent for the vinyl ether, as for example in the presence of saturated ethers or of hydrocarbons of the aliphatic, hydroaromatic or aromatic series, but an advantage of this modification is that substantial quantities of solvents for the vinyl ether are not necessarv.

The properties of the polymerization products obtainable in this manner are very -similar to those of the products obtained as hereinbefore described by means of the other said acid condensing agents; they may, however, be obtained in an entirely colourless form. As the last traces of the vinyl ether are only polymerized with difliculty, the products first obtained are in some cases still unsaturated to a slight extent. After being allowed to stand for some time or after removing the last traces of non-polymerized vinyl ether in vacuo, the polymerization products be-. come quite inert to bromine. Any small amounts of boron halide addition products which may be present are readily removed by treating the poly- Also'this polymerization of the merization products with steam and then drying them.

The most satisfactory temperatures for the polymerization of the vinyl ethers when employing addition products of boron halides lie between about 40 and 60 C. The polymerization merized ethers according to the present invention is soluble in water as for example the poly meric vinyl methyl ether, the vinyl ether of di- .ethylene glycol mono-ethyl'ether and the vinyl ether of ethylene glycol mono-ethyl ether, the

first mentioned compound-preferably, however,

for waxes.

with theconjoint employment of a dissolution a s sistant such as methyl. or ethyl alcohols or ethylene glycol mono-methyl ether; these compounds may find useful application in sizing or dressing. The higher members, such as the polymeric octodecyl vinyl ether, are white, waxy bodies which are generally easily soluble in gasoline, benzene, turpentine oil and like solvents The followingexamples will further illustrate how this invention may be carried out in practice but the invention is not --restricted to these ex-' amples. The parts areby weight.

' Example 1 0.25 part of stannouschloride is added 50' parts of vinyln-butyl ether (CHz'=CH--O-C4Hs',

which may be prepared by heating anhydrous nbutanol with vinyl chloride'at C. in an auto;

clave in the presence of metallic sodium? in, a reaction vessel provided with a wide reflux condenser. After a few minutes the temperature begins to rise and at a temperature of about 45 to 50 C, sudden boiling with a consequent rapid rise in temperature to C.-takes place. The

reaction product is a yellowish brown balsam-- like masswhich is purified by steam distillation.

35 parts of a viscous liquid yellow polymerization product are obtained.

Tin tetrachloride or aluminium chloride may be-employed instead of stannous chloride.

Example 2 1 part of aluminium chloride is'suspended in 200 parts of dry benzene and then 200 parts of vinyl ethyl ether (CH:=CHO-C2H5) are added to the suspension while stirring. About 20 parts of the vinyl ether are added at once in order to start the reaction, the remainder being added a little at a time. The occurrence ofturbidity indicates the commencement of the polymerization. when the temperature has risen to from 60 to 80 C. the vinyl ether is added in portions of from 1 to 2 parts, whereby the fact that the re-' action is taking place may be detected not only by a rise in -temperature but also by a brown colouration of the mass which disappears'after the reaction. When the colours-tion has disappeared, further amounts of. vinyl etherare added, and this procedure is repeated. When all the vinyl ether has been introduced; the whole is stirred for an hour at 80 C. 1 The volatile constitiients are distilledofffrom the resulting mixture with steam and the residue is taken up with ethyl ether. After drying and distilling of! the ether, 144 parts of a yellow balsam-like product are obtained. w

I Example 3 20 parts of ethyl-n propenyl ether 1 (CH3-CH=CH--O-C2Hs) point of the benzene and the reaction-mixture assumes a brown colour. When the whole of the ether has been introduced, the benzene and v'oiaresidue is taken up with ether, and the ethereal solution is shaken up with animal charcoal and filtered. After distilling off the ether, a brownish'yellow, soft resin remains behind.

' Example 4 I 1 part of aluminium chloride is suspended in 1 parts of benzene, 50 parts of ethyl-isopropenyl ether ,are allowed to drop slowly into the suspension.

Thetemperature rises to the boiling point of the benzene and the reaction mixture assumes a I brownish red colour. After distilling off the benzene and volatile constituents with steam, a

brown, very sticky mass resembling a vegetable balsam remains behind, the behaviour of which towards. solvents is generally; speaking the same as the polymerization product obtained from vinyl ,ethyl ether.

Example 5 14 parts of vinyl ortho-cresyl ether which may be prepared by heating sodium orthocresolate with vinyl chloride in the" presence of ethyl alcohol to C. in an autoclave) are allowed t'o drop gradually into aisuspension of 0.3 part of aluminium chloride in 40 parts of benzene, whereby the polymerization commences with the evolution of much heat and the formation of a red colouration: The diluent and the volatile constituents are distilled oif with steam and, after cooling, the water is poured 01f from the residue. The reaction product is a violet coloured brittle resin which is soluble in ethyl ether,

. acetone, 96 per cent ethyl alcohol, butyl acetate and hydrocarbons of the benzene series butwhich is scarcely soluble in. benzine.

If vinyl phenyl ether be employed instead of vinylortho-cresyl ether, a'solid red polymerization product is obtained which is soluble only with dimculty in the said solvents with the exare allowed to stand at room temperature after the addition of 5 parts of zinc chloride. After having been allowed to stand for 2 days, the original readily'mobile liquid has. been converted into a colourless, balsam-like, very sticky resin.

tile constituents are expelled with steam. The

The polymerization product is readily soluble in ethyl ether, acetone, butyl acetate and benzene Example 100 parts of vinyl ethyl etherare introduced into a vesselprovided with an eflicient stirring device, a cooling jacket and a reflux condenser. The ether is warmed to 35 C. and 0.5 part of a 2 per centsolution of the addition'product of boron fluoride and -di-n-butyl ether (which boils at 160 C.) in di-n-butyl ether is added. 2000 parts of vinyl ethyl ether are allowed to flow in at from 40 to 50 C. during the course of 2 hours while a further 3.5 parts of the said solution of the addition product of boron fluoride and di-n-butyl ether are gradually added at the same time. The resulting colourless, viscous liquid polymerization product is freed from the last traces of non-- polymerized vinyl ether at about 50 C. in vacuo. The final product is quite stable'to bromine.

Example 8 100 parts of vinyl-n-butyl ether are introduced 7 into the stirring vessel described in Example "I of 2 hours.

and, after warming to 40 C., 0.5 part of a 2 per cent solution of the addition product of boron fluoride and di-ethyl ether in di-ethyl ether is added. The temperature of the polymerization which soon commences is kept at about 40 to 50 C; partly by cooling and partly by the addition of further amounts of vinyl n-butyl ether cooled to a temperature of 15 C. In this manher about 2000 parts of vinyl butyl ether and a further 3.5 parts of the solution of the boron fluoride addition product are added in the course After stirring for about a further2 hours, the polymerization is practically completed. The last traces of non-polymerized vinyl butyl ether are polymerized after allowing the reaction ,mixtureto stand for several days at room temperature or slightly elevated temperatures, as for example about 40 C. A colourless, honey-like highly viscous and sticky product is obtained.

1n the same manner'vinyl cyclohexyl ether may be polymerized by substituting the aforesaid quantity of vinyl butyl ether by the same quantity of the cyclohexyl ether;

Example 9 100 parts of vinyl methyl ether and 1 part of the solution of the boron fluoride addition product employed in Example 7 are introduced into the vessel described in Example 7, the reflux.

condenser of which is kept at from 5 to 0 C., and ,heated to boiling. As the polymerization proceeds, the temperature of the contents of the vessel gradually rises from 9 C. -(the boiling point of vinyl methyl ether) to about 20 C.

1000 parts of vinyl methyl ether are, then added atabout 20 C. during the course of 4 hours while 1 part of the solution of the said polymerizing agent is gradually added at the same time. The contents of the vessel are thenheated to 30 C. until a sample withdrawn and dissolved in cyclohexane only absorbs small amounts of bromine. Remainders of non-polymerized vinyl methyl ether are removed from the polymerization product by distillation in vacuo at about 200 millimetres of mercury.

The resulting polymerization product is easily soluble in organic solvents such as aliphatic alcohols, ketones, esters or acids and in hydrocarbons and is miscible with water in any desired proportion. In the latter case it is, however, advantageou's to employ a dissolution assistant such as methyl or ethyl alcohols, ethylene glycol monomethyl or ethyl ethers. Viscous mixtures of equal parts of the polymerization product with the dissolution assistants can be diluted with water inany proportion with the formation of clear solutions.

Almost the same polymerization product is ob tained by heating vinyl methyl ether and the said polymerizing agent to about 60 C. in an autoclave for from about 4 to 6 hours.

Example 10 200 parts of vinyl octodecyl ether CH2=CHOC18H37 obtainable from octodecyl alcohol and acetylene at -from about to C. in the presence of a small quantity of caustic potash, are fused in a stirring vessel. 0.6 part of the solution of polymerizing agent specified in Example 7 is added,at 50 .C. and the vigorous reaction which immediately commences is kept at a temperature of from 50 to 60 C. by cooling. 2000 parts of vinyl octodecyl ether together with 2.5 parts of the said solution of the polymerizing agent are gradually added during the course of 3 hours. .The resulting saturated, solid polymerization product melts at 55 C. and resembles in its appearance colourless translucent paraflin wax.

In thesame manner octyl, decyl, dodecyl and tetradecyl ethers of vinyl alcohol as well as the vinyl ethers of .oleic alcohol and of the alcohols corresponding to the acids of Montan wax can be polymerized. If desired; a 2 per cent solution of boron fluoride in acetic acid may be employed as polymerizing agent.

Example 11 10 parts of octodecan -diol divinyl ether (c18H36(o-cH=cH2)2); obtainable by acting with acetylene at a temperature of from 160 to 180 C. in the presence of 2 per cent of caustic potash on octodecan -diol (obtainable by catalytic hydrogenation of caster oil at a temperature of from 230 to 250 C. under a pressure of hydrogen of about 100 atmospheres), are dissolved-in 800 parts of vinyl ethyl ether.

100 parts of the solution obtained are introduced into an enamelled vessel provided with an eflicient stirring device, a cooling jacket and a reflux condenser. The solution is warmed to boiling (about 36 C.) and 0.6 part of a 1 per cent solution of the addition product of boron fluoride and di-n-butyl ether in di-n-butyl ether is added. The vigorous reaction is kept moderate by cooling to 40 C. The residual 710 parts of the solution are allowed to flow in during the course of 2 hours whilea further 2.4 parts of the said solution of the addition product of boron fluoride and di-n-butyl ether are gradually added at the same time. Remainders of non-polymerized vinyl butyl ether, if such be still present, are removed by distillation in vacuo at about 100 ,millimetres of mercury.

The polymerization product obtained is very tenacious and stringy and resembles synthetic rubber; in contrast to the product obtained according to Example 7 it is insoluble in organic solvents-such as aliphatic cycle-aliphatic and aromatic hydrocarbons, as'ior example benzine,

.cyclohexane, benzene, ethyl alcohol or acetone,

but swells therein.

Example 12 An internally enamelled vertically arranged tubular reaction vessel having a sheet metal vessel for vinyl ether and-an outlet pipe are led 'sel. Non-polymerized vaporous jacket capable of being heated, is filled with glass beads of abdut 1 centimetre diameter to each litre of which cubic centimetres of the bleaching earth obtainable in commerce under the trade name Granosil are'uniformlyadded. The temperatu're'in the vessel is kept at about 70 C. by means of hot water circulating in the heating jacket. The supply pipe from a storage through the closure at the upper end of the vesvinyl ethyl ether escapes through the said outlet, is liquefled in a condenser arranged above the .said storage vessel and is supplied to the said vessel again. The heat of polymerization of the vinyl ether is to a large extent withdrawn by the heat required for evaporating the non-polymerized fraction of the vinyl ether. A vessel for collecting the polymerization product is arranged in an airtight manner at the bottom of thereaction vessel. About 500 grams of liquid vinyl ethylether per hour and per litre of reaction space are supplied ,to' the reaction chamber from the storage vessel; about 150 grams of polymerization product are obtained while the non-polymerized vinyl ethyl ether passes back into the storage vessel again by way of the condenser- The resulting polymerization product, which generally still contains small amounts of non-polymerized ether dissolved therein, becomes quite inert to bromine after standing for some time. If a further purification be desired, the polymerization product may be redissolved in a suitable solvent; such as benzene or cyclohexane.

A similar result is obtained when gaseous vinyll ethyl ether is introduced, the polymerization product and the non-polymerized vinyl ethyl- About 100 grams per hour and per litre of re-- action space of vi'nyl-n-butyl ether are allowed "to fiow at about 70 C. into the reaction vessel filled with GranosiP' and glass beads as described in Example 12. The polymerized vinyl butyl ether is withdrawn from the lower end of the reaction vessel and becomes quite stable to bromine after standing for some time.

Example 14 5 parts of the divinyl ether of octodecandiol are dissolved in 1000 parts of benzene or benzine and 05 part of a 1 per cent solution-of boron fluoride in di-n-butylether are added. The reaction mixture grows warm and viscous and solidifies to a solid jelly, from which the benzene. or benzine can be removed by pressing. A similar product can be 'obtai'ned from the divinyl ether of triethylene glycol Example 15 h proportion.

mdi-butyl ether is added at 40 C. to 100 parts of the vinyl ether of diethylene glycol monoethyl ether fCH2=CHOCHz -CH2O- V CHz-CHa-O-CzHs obtainable by acting with acetylene on diethylene glycol mono-ethyl ether in the presence of 2 per Example 16 0.05 part Ma 2 per cent solution of the double compound of boron fluoride and di-butyl ether in di-butyl ether is added to 5 parts of di-vinyl ether (CHz=CH'-O-CH=CH2). With a slight evolution of heat the whole solidifies to a solid,

brittle mass.

What we claim is: a

1. The process for the polymerization of vinyl ethers, corresponding to the general formula R2/ O-R in which R denotes a radical selected from the group consisting of aliphatic, aromatic or hy- 2. The process for the polymerization of vinyl ethers, corresponding to the general formula R1\ /R:I

group consisting of aliphatic, aromatic or hydroarofnatic hydrocarbon radicals and the radi-,

cals of the glycols and polyglycols and the monovinyl, monovinylalkyl, monoalkyl, monocycloalkyl and monoaryl ethers thereof and R1, R2 and R3 denote hydrogen or alkyl radicles, which comprises contacting the said ethers with from 0.001- to 5 per cent of their weight of an inorganic acid reacting condensing agent.

3. The process for the polymerization of vinyl ethers, corresponding to the general formula N I,

. so in which R denotes a radical selected from the in-which R denotes a radical selected froin the group consisting of aliphatic, aromatic or hy-.

droaromatic hydrocarbon radicals. and the radicals' of the glycols and polyglycols and the monovinyl,. monovinylalkyl, monoalkyl, monocycloalkyl and monoaryl ethers thereof and R1, R2 and Ra denote hydrogen or alkyl radicles, which comprises contacting the said ethers with from 0.001 to 5 per cent of their weight of an inorganic acid in which,R denotes a radical selected from the group consisting of aliphatic, aromatic or hydroaromatic hydrocarbon radicals and the radicals of the glycols and polyglycols and the monovinyl, monovlnylalkyl, monoalkyl, monocycloalkyl and monoaryl ethers thereof and R; R2 and 5 Rs denote hydrogen or alkyl radicles, which comprises contacting the said ethers with from 0.001 to 5 per cent of their weight of an inorganic acid reacting condensing agent at a temperature between 10 and 120 C.

o 5. The process for the polymerization of vinyl ethers, corresponding to the general formula 25 in which R denotes a radical selected from the group consisting of'aliphatic, aromatic or hydroaromatic hydrocarbon radicals and the radic'als of the glycols and polyglycols and the monovinyl, monovinylalkyl, monoalkyl, monocycoalkyl and nionoaryl ethers thereof and R1, R2 and R3 denote hydrogen or alkyl radicles, which comprises contacting the said ethers in the liquid phase with a small amount of an inorganic acid reacting condensing agent;

35 6. The process for the polymerization of vinyl ethers, corresponding to the general formula in which R denotes a radical selected from the .group consisting of aliphatic, aromatic or hydroaromatic hydrocarbon radicals and the radicals of the glycols and polyglycols and the monocondensing agent.

7. The process for the polymerization of vinyl ethers, corresponding to the general formula in which R denotes a radical selected from the group consisting of aliphatic, aromatic or hydroaromatic hydrocarbon radicals and the radicals of the glycols and polyglycols and the monovinyl, monovinylalkyl, monoalkyl, monocycloalkyl and monoaryl ethers thereof and R1, R2 and R3 denote hydrogen or alkyl radicles, which comprises contacting the said ethers in the vaporous state with a smallamount of an inorganic solid acid reacting condensing agent at a temperature up to 250C.

8. As a new article of manufacture, a polymeric vinyl octodecylether which is practically inert to bromine.

9. Articles of manufacture consisting essentially of polymeric vinyl alkyl ethers which are viscous liquid to solid saturated substances, stable to dilute aqueous acids and alkalis, and practically inert to bromine.

10. Articles of manufacture essentially comprising polymeric vinyl ethers which are viscous liquid to solid saturated substances-stable to dilute aqueous acids and alkalis, being the polyviscous liquid to solid saturated substance stable to dilute aqueous acids and alkalis, and practically inert to bromine.

WALTER REPPE. OTIO SCHLICH'I'ING. 

